Device for the flow control of media, particularly contaminated liquids and/or gases

ABSTRACT

A valve structure for controlling the flow of poisonous and/or contaminated media into a container, comprising two vertically aligned valve bodies releasably connected with each other and containing each an axially slidable closure piston, whereby these two pistons are releasably and sealingly connected with each other at their opposite end faces and of which the upper piston is provided with a lengthwise extending actuating rod extending with circumferential clearance lengthwise through a tubular portion of the upper valve body which tubular portion is connected to a media supply pipe. In one position of the sealingly connected closure pistons the path of flow through the valve structure is closed, while in another position of the connected closure pistons the path of flow is open when the actuating rod has moved the pistons downwardly so far as to connect transverse ports in the lower valve body and to connect these transverse ports at the same time with the interior of the container into which extends the lower valve body.

United States Patent 1 91 1111 3,785,404

Gappisch et al. [45] J 15, 1974 [54] DEVICE FOR THE FLOW CONTROL OF 3,359,015 12/1967 Zahuranec 25l/l49.8 X

MEDIA, PARTICULARLY CONTAMINATED FO IG PATENTS O APPLICATIONS ,LIQUIDS AND/OR GASES 352,205 3/1961 Switzerland l37/614.04

[75] inventors: Max Gappisch, Karlsruhe-Durlach; 615,121 1 /l961 ltaly 137/614.06

Friedrich Clans Walter, Ettlingen,

Baden; Horst lPoll h Primary Examiner-Samuel Scott Malsch-Sulzbagh, ll f Germany Assistant Examinerlra S. Lazarus Arr H'l1,Sh ,M ',o &s' 731 Assignee: Argus Gesellschaft mbH, Omey emm toss mpson Etlingen/Baden, Germany 57] ABSTRACT Filed; June 6, 1972 A valve structure for controlling the flow of poisonous and/or contaminated media into a container, compris- [2]] App" No" 260,251 ing two vertically aligned valve bodies releasably connected with each other and containing each an axially Foreign Application Priority Data slidable closure piston, whereby these two pistons are June 11, 1971 Germ n P 21 23 9 73 releasably and sealingly connected with each other at Mar. 14, 1972 Germany P 22 12 176.2 their pp nd a s a d f hich t e upp r piston is provided with a lengthwise extending actuating rod [52] [1.5. CI 137/614, 137/614,, 137/625 33, extending with circumferential clearance lengthwise 251/148 through a tubular portion of the upper valve body [51] Int. C1. F16135/00 which tubular p r i n i conn cted to a media supply [58] Field of Search 137/614, 614.01, pip n n po i i n f he sealingly connected clol37/6l4.02, 614.03, 614,04, 614 ()5, 614,06, sure pistons the path of flow through the valve struc- 614.11, 614.12, 614,13 6l4,21; 251/146, ture is closed, while in another position of the conl49.8, 149.9, 148, 325, 625,38, 625,48, nected closure pistons the path of flow is open when 625,49, 375 the actuating rod has moved the pistons downwardly so far as to connect transverse ports in the lower valve [56] Referen e Cit d body and to connect these transverse ports at the UMTED STATES PATENTS same time with the interior of the container into which 2,556,337 6/1951 Paille l37/614.l9 x extends the lower valve b 1,968,421 7/1934 Proctor 137/614 X 15 Claims, 8 Drawing Figures I ass 350 so J 5 PAIENTEUJANI 52:1?

sum 3 OF 4 ll IDEVIIEE EOE 'lllHIE lFlLOW CONTROL OF MEDIA, PARTKCIUEAIREY EONTAMENATED LIQUIDS AND/OE GASES The invention relates to a device for the flow control of media with two valve bodies formed each of a housing part and a closure piston slidable axially in the same, in which the housing parts and closure pistons are slidable in contact surfaces which do not come into contact with the medium to be flow controlled and are exposed in the uncoupled condition of the valve bodies, are connectable, and in which the connected closure pistons are movable together between a first end position shutting off the path of flow, while in a second end position a passage path is opened through the device. This device is to be suitable and intended to a particu' lar degree for the control of the flow of poisonous and- /or contaminated media.

In separable flow control devices, with which the flow of poisonous and/or contaminated media are to be controlled, it is important that after the separation, the outer surfaces of the valve bodies connected with one another are at the separation points free from poisonous wetting with the medium or are free from contamination, respectively. The problem of the separability with outer surfaces not wetted or contaminated, respectively in the separated condition of the parts of the device is in a flow control device of the invention not as yet published already solved to the extent that two connectable valve bodies are associated with a first and second closure piston movable along an axis of the same, which from a first end position corresponding to the separated condition, which tightly shutting off the valve bodies with respect to the surroundings, are movable into a second position in which a flow passage is opened through the valve bodies and thereby with their end surfaces which in separated condition of the valve bodies face the surroundings are closely connected with one another.

Although with this solution of the invention, the problem of the furnishing of a separable flow control device, whose end surfaces of the valve bodies in separated condition are not contaminated or wetted with medium, respectively, is fundamentally solved, the aforementioned device can still not be regarded as utilizable for the practical introduction in the art because upon the actuation of the closure pistons constructed as cylinders, the apertures of the transverse channels disposed in the same must pass the seals surrounding the closure pistons. This can easily lead to a rapid wear of the seals and therewith to an endangering of the persons servicing the flow control device. During the flow control of contaminated and/or poisonous substances, however, an absolute safety is required. Accordingly it is an object of the invention to improve a flow control device of the type mentioned, particularly with respect to the safety requirements when introduced for commercial use.

Starting with a flow control device described at the beginning, the object of the invention is obtained when the one closure piston is provided with a closure member and with a cylindrical part having a flow path extending lengthwise of the valve body, while the closure member, which cuts off the path of flow in a sealing plane disposed in the rear of the connecting plane between the two valve bodies, is axially slidably guided, and that the sliding path of the cylindrical part is limited in such manner, that upon the movement of the other closure piston and the closure part connected therewith into the second position the closure part is lifted from the sealing surface of the cylinder part and opens the flow path.

In contrast to the device described initially, and from which the present invention emanates, the closure pistons which are axially slidable in connected condition within the housing parts are not provided with any transverse bores or channels whatsoever, whice would extend as flow paths for the medium to be flow controlled through their sleeve surfaces. The closure pistons which have all the same cross section, have completely smooth sleeve surfaces, so that during their movement from the first end position in which the flow paths are closed off in both valve bodies, into the second end position no wear of the seals surrounding the closure pistons can occur. Only after the contact surfaces between the one closure piston and the closure piece of the other closure piston as well as the sealing surfaces between closure piece and cylinder part of the last named closure piston have passed the seals and are introduced into a chamber provided with flow channels of the one valve body, the closure piece is lifted from thesealing surface of the cylindrical part and is moved with the other closure piston connected thereto into the second end position. The axial movement of the cylindrical part and of the closure piston associated with the closure member is thereby halted in a position located in front of the second end position, so that a flowthrough-path in the form of an annular gap is formed between the closure member and the annular surface of the adjacent cylindrical part.

According to another object of the invention, the closure member forming with the aforementioned cylindrical part, the closure piston of the one valve body may be provided with an actuating rod extending lengthwise through the cylindrical part, by means of which the movement of the closure member and of the closure piston of the other valve body connected therewith in operative condition may take place in the end position permitting a flow through the flow path or the return movement from this end position into the sealing position with the cylindrical part.

According to another object of the invention, the actuating rod may comprise a pipe whose bore forms the flow path through the cylindrical part, whereby it is of advantage that the closure member is supported axially slidably in the cylindrical part of the closure piston.

Still another object of the invention is that the closure member may be held positively connected in sealing support in such manner on the sealing surface shutting off the flow path through the valve body that the release of the flow path takes place only when the cylindrical part on account of the axial movement of the two connected closure pistons has performed its maxi mum movement in the direction toward the second end position. To this end, the closure member may be held in closure position by means of an initially tensioned compression spring, the compression of which can take place only after the cylindrical part engages a stop member which limits the axial movement.

Within the framework of the present invention, any means suitable for a fixed, however releasable connection of both valve bodies may be employed. In order, however, to prevent with assurance, an accidental separation of the two valve bodies, while the closure pistons of the device are in a flow controlled position in which the flow-through passages are open, it was found to be advisable to provide locking means for the connection of the housing parts, and for the closure piston disposed in locking position, which in the other end position of the closure piston, in which the flow through paths in the valve bodies is shut off, releases the connecting means for the movement in a non-connected position, in which a danger free separation of the valve bodies may take place.

In further development of these objects of the invention that the connecting means for the connection of the housing parts may comprise a coupling sleeve which is connected axially fixedly and rotatable with the one housing part and may be connected positively with the other housing part, and has an actuating ring, which with the actuating lock held in the locking position is freely rotatable as compared with the coupling sleeve, on the other hand, is however rotatable with the latter, when the actuating lock is not disposed in locked position.

For example, the coupling sleeve may be constructed as a screw cap with which the actuating ring is axially slidable and is associated in its one end position to be positively connectable. The actuating lock may comprise a locking element of the slidable key type with a key as locking element slidably guided transversely to the longitudinal direction of the housing part with which the actuating ring is associated, said last mentioned key cooperating on the one hand with a wedge surface of the actuating ring and on the other hand with a section of the closure piston axially slidable within the housing part, when the latter is disposed in the position opening the flow passage in the valve body.

Further details, advantages and particular features of the invention will be explained with reference to a few embodiments illustrated by way of example in the accompanying drawings, however without serving as a basis for a restriction of the invention to the embodiments shown. The figures illustrate diagrammatic views of longitudinal sections.

IN THE DRAWINGS:

FIGS. la and 1b show each a valve body ofa first embodiment, which are connectable with one another.

FIGS. 2a and 2b show each a flow control device formed by connecting the valve bodies shown in FIGS. 1a and lb. FIG. 2a illustrates a closed flow path, while FIG. 2b shows an open flow path.

FIGS. 3a and 3)) show a second embodiment in views similar to FIGS. and 2b, and

FIGS. 4a and 4b illustrate in partial sections a third embodiment of the device of the invention.

Referring to the FIGS. la and 2b, the device comprises two axially aligned valve bodies 310 and 311. The valve body 311 is inserted tightly in the neck of a container only indicated at 312 and has a housing part 313 and a closure piston 314 which is axially slidable in the bore of the housing part 313. The lower end face of the closure piston 314 which is disposed opposite the upper end face 315 is fixedly connected with a ring 317, which engages an annular abutment in the housing part 313 and limits the axial movement of the closure piston 314 in a direction toward a flange 316 at the upper end of the valve body 311. Between the ring 317 and a cover 318 threaded into the lower end of the valve body 311 is arranged a compression spring 319 (FIG. lb) holding the closure piston 314 in the closure position. In the range of the bore for the closure piston 314 are arranged in the wall of the housing part 313 the transverse channels 320, 321 which communicate with the inner chamber of the container 312. Between the channels 310, 321 and the flange 316 of the housing part 313 is arranged in an annular groove a seal 322 which surrounds the closure piston 314. Another seal 323 is arranged adjacent the separating plane in the upper end of the housing part 312 and surrounds the upper end of the closure piston 314. Furthermore, there is arranged in the upper end of the closure piston 314 a threaded bore 324 communicating with an enlarged guide bore 325.

The valve body 310 comprises a housing part 330 having axially slidably therein a closure piston 331 which in contrast to the embodiment described above is formed of a hollow cylindrical part 332 and a cylindrical closure part 333. From the lower end face 335 of the closure part 333 a guide pin 336 and a reduced threaded pin 337 extend downwardly. This guide pin 336 and threaded pin 337 are adapted to be connected with the guide bore 325 and threaded bore 324 of the closure piston 314. The cylindrical part 332 extends upwardly from the housing part 330 and from a flange 334, on the latter. The lower part of the cylindrical part 332 has a central bore 338, the upper end of which communicates at a distance from the housing part 330 with a pipe 339, which is inserted in a transverse bore of the part 332 and serves for the introduction or discharge respectively, of the medium the flow of which is to be controlled. The section of the hollow cylindrical part 332 connected to the closure member 333 has the same cross section as the closure member 333 and is sealed from the same by a sealing surface 340. The sealing surface 340, when the valve bodies are separated, lies in the range of a guide bore in the housing part 330, in which are arranged annular seals 341 and 342 disposed in annular grooves to both sides of the sealing surface 340, (FIG. la). Finally, there is arranged in the lowermost end of the housing part 330 an annular seal 343 surrounding the lower end of the closure member 333.

On the upper end of the closure part 333 which is remote from the lower end face 335 extends a rotatable and axially slidable actuating rod 345 which is fixedly connected with the member 333. The rod 345 extends through the hollow cylindrical part 332, which is provided with an axial bore 338 and is sealed by an annular seal 346 and at its uppermost end projects from the cylindrical part and has attached thereto an actuating handle 347. As shown particularly in FIG. 2a, a sleeve 348 connected in the vicinity of the actuating handle 347 with a reduced portion of the cylindrical part 332, and a helical pressure spring 349 surrounding the rod 345, urges the closure member 333 into the closure position. Furthermore, an arresting pin 350 in a transverse bore of the sleeve 348 engages an annular groove associated with the rod 345. Finally, there is associated with the cylindrical part 332 an end position lock comprising locking balls 353 engaging recesses of the cylindrical part and held in place by a slidable sleeve 352. The sleeve 352 is axially slidable against the action of a helical spring 354 in such manner that the locking balls 353 may shift somewhat radially and an axial movement of the cylindrical part 332 may take until the annular end faces 355, 356 (FIG. 1a) engage each other.

In the connected or coupled condition of the valve bodies, the flanges of the same are releasably connected with each other by a clamp 3611 and the closure pistons are connected with each other in that the threaded pin 337 is threaded into the threaded bore 324. When this has taken place the end surfaces of the housing parts 313, 331) sealed by the seals 323, 343 and the end surfaces 315, 335 of the closure pistons are pressed sealingly against one another. If now the locking of the cylindrical part 332 is released by an axial movement of the sliding sleeve 352, the connected closure pistons may be axially pushed in the direction toward the cover 318 until the annular end faces 355, 356 engage each other whereupon the balls 353 in this operative position engage associated recesses in the cylindrical part 332 and arrest the closure pistons anew. The annular sealing surface 3411 is then located in the range of the transverse channels 321), 321 of the valve body 311. Now the arresting pin 3511 is removed and the rod 345 is pushed axially in the same direction. This results in a release of the closure member 333 from the sealing surface 340 of the cylindrical part 332 and an annular gap 361 (FIG. 2b) is formed communicating with the transverse channels 321), 321.

The closure piston 314 is then located in the end position illustrated in FIG. 2b and the pipe 339 introduces the medium into the bore 333, the annular gap 361 and the transverse channels 320, 321 and finally the medium flows into the container 312.

For the purpose of closing the flow paths, first the closure member 333 by means of the rod 345 and the action of the spring 349 is brought into sealing engagement with the annular sealing surface 340 of the cylindrical part 332 and the rod will be arrested by means of the pin 3511, whereupon during a reversal of the above described actuating procedures, the connected closure pistons will be returned to the position shown in FIG. 2a. Thereafter, the clamp 3611 may be released and the threaded pin 337 is unthreaded from the threaded socket 324, and now a separation of the valve bodies may take place. The end surfaces 315, 335 of the closure pistons and the corresponding end surfaces of the housing parts 313, 330 are then free from any moistening of the flow controlled medium or free from any contamination, respectively.

In the embodiment of the device of the invention as shown in the FIGS. 3a and 3b, similar parts are provided with reference characters as in FIGS. 1a to 2b, except that they are increased by one hundred, whereby in place of an actuating rod a pipe 445 extends from the closure member 433, which by means of a transverse pin 471) is axially connected with an actuating handle 447 constructed as cylinder.

A pipe nipple 439 is arranged in axial alignment with the pipe 445 in the actuating handle 447 by means of a transverse pin 471. The actuating handle 447 has a lower hollow cylindrical portion 472 extending into the housing part 430, and guided between the walls of the housing part 4311 and the cylindrical part 432. For shielding of the inner chambers moistened by the flowing medium against the surroundings are employed the annular seals 473, 474, 475. The pipe 445 is provided in the vicinity of the lower sealing surface 440 with transverse ports 476.

The two valve bodies 410, 411 are again connected with each other by a threaded pin 437 on the closure member 433 which is threaded into the threaded bore 424 in the closure piston 414, and by an annular clamp 460 engaging the meeting flanges 416, 434 of the housing parts 411 and 4311. The connected closure pistons are in the manner described above in connection with the FIGS. 2a and 2b, axially movable up to the engagement of the annular stop surfaces 455, and 456, with each other, whereby in the one end position the transverse ports 476 in the pipe 445 are flush with the transverse channels 420 and 421 in the lower housing part 413. Upon a further axial movement of the closure parts in the same direction in which the cylindrical part 431 no longer takes part, the pressure spring 449 will be compressed between the cylindrical part 432 and the actuating handle 447, and the closure part 433 is moved away from the annular sealing surface 441), so that again an annular gap 461 is formed.(FIG. 3b). In this end position there takes place again axial locking by the engagement of the arresting balls 453 in corresponding recesses in the sleeve of the actuating handle 447. Now a flow of the medium into the interior of the container 412 can take place in the same manner as in the device illustrated in FIGS. 1a to 2b by the sleeve 439 and the channel 438 formed by the pipe 445.

The advantage of this form of construction consists in the positive sequence of all operating steps, so that sources of danger on account of faulty manipulation are avoided.

The embodiment of the device of the invention as shown in the FIGS. 4a and 4b correspond to the construction similar to the device illustrated in FIGS. 3a and 3b. Therefore, the same parts are again provided with the same reference characters, however, increased by another one hundred.

In this embodiment shown in the FIGS. 4a and 4b, in place of the annular clamp shown diagrammatically in FIGS. 3a and 3b, the housing parts 513 and 531) are axially connected by connecting means 560 and the valve body 511 is fixedly secured by means of a cap-shaped nut 580 with the neck of a container 512 by the interposition of an annular seal 581. The neck of the container in this embodiment includes the portion of the valve body 511 extending into the interior of the container 512 with radial spacing and with the annular gap 582 formed in this manner communicate with the channels 521 for the passage of the medium to be flow controlled.

The connection means 560 for the tight, but releasable connection of the housing parts comprises a screw cap 534, which engages the rear face of a flange 534 on the housing part 530 and is threaded onto the exterior thread 585 of the housing part 511, and also comprises an actuating ring 536 axially slidable relative to the screw cap 584 having a sleeve-shaped recess surrounding a portion of the screw cap. The axial movement of the actuating ring 586 is limited by means of a holding ring 587 which is mounted in an annular groove in the cylindrical guide surface of the screw cap, and engages in a shallow annular groove 588 which is provided in the guide surface of the sleeve shaped portion of the actuating ring and has an axial extent corresponding to the desired movable path. In addition, there extend from the flange of the actuating ring 586 a few actuating pins 589 axially in direction of the flange of the screw cap 584, which latter is provided with socketshaped bores 590, whose position matches those of the actuating pins 589 which enter the bored 590 for the purpose of coupling the actuating ring 586 with the screw cap 584, when the actuating ring 586 is pushed into the connecting position as shown in FIG. 4a. FIG. 4b illustrates the disconnected position of the parts 584 and 586.

The actuating lock of the actuating ring 586 consists of radial locking bolts 591, which are slidably mounted in the housing part 530 of the valve body 510 transversely to its longitudinal axis and cooperate with a conical cam surface 592 on the inner surface of the flange of the actuating ring 586. Each locking bolt 591 has a conical head 593 which engages the conical cam surface 592, and as shown in FIG. 4a may extend with a portion through the wall of the housing part and into the inner chamber of the valve body surrounded by the housing part, when the closure piston 531 is located in its position shutting off the flow passage in the valve body (FIG. 4a). If, however, the closure piston is pushed into the flow permitting position, a conical surface 594 of the closure piston engages the inner portion of the radial locking bolts 591 projecting into the inner chamber of the housing part and moves the bolts 591 radially outwardly, so that the conical heads 593 of the locking bolts act as cam members on the cam surfaces 592, 593 and axially move the actuating ring 586 into an end position away from the screw cap 584. As long as the closure piston 531 is positioned in the flow permitting position shown in FIG. 4b, the actuating ring is arrested in its position axially remote from the screw cap, and the actuating pins 589 are out of engagement with the socket-shaped bores 590 of the screw cap 584, so that an actuation of the same cannot take place by rotating of the actuating ring 586. This is possible only after the closure piston 531 has been moved back into the position shown in FIG. 4a in which position the flow paths in the valve bodies are closed.

What we claim is:

l. A flow control coupling for transferring contaminated media from one container to another comprising first and second separate housing parts having end faces couplable together in abutted position and releasable means for maintaining the coupled housing parts in coupled abutted relationship, each of said housing parts having coaxial equal diameter bores therein receiving axially movable pistons, one of said pistons having a cylindrical part with a bore therein closed at one end by a first end face of a separate, independently movable, closure member, the closure member attached to an actuatable member axially movable within the bore of the cylindrical part, a second end face of the closure member forming an end surface of the first housing part when the housing parts are separated, a flow path through said housing parts closable by said closure member when the first end face of the closure member closes the bore of the cylindrical part, the closure member movable away from the cylindrical part to open the bore and the flow path when the housing parts are coupled together, the closure member movable into the bore of the second housing part.

2. The device of claim I, wherein the actuatable member comprises an actuating rod extending through the cylindrical part and having one end thereof attached to the closure member.

3. The device of claim I, wherein the actuatable member comprises a tube forming a flow channel, the

tube extending through the cylindrical part, the tube having transverse flow ports disposed within said cylindrical part, the tube having one end thereof attached to the closure member, and portions of the tube containing the transverse flow port projectable from the cylindrical part.

4. The device of claim 1, including means urging the closure member against the cylindrical part to maintain the bore of the cylindrical part closed by the first end face.

5. The device of claim 4, wherein the cylindrical part is slidable within the associated housing part and has means associated therewith limiting movement of the cylindrical part whereby the cylindrical part and the closure member are movable together in sealed relationship for a limited distance with respect to the housing part in a first direction, the closure member movable beyond the cylindrical part in the first direction.

6. The device of claim 5, wherein means are provided preventing movement of the closure member independent of the cylindrical part until the cylindrical part has moved to a fixed position.

7. The device of claim 5, wherein the cylindrical part is movable from a closed position to an openable position and means are provided for moving the closure member with the cylindrical part in sealed relationship therewith from the closed position to the openable position, the closure member being movable beyond the openable position to open the flow path when the cylindrical part is in the openable position, and means inhibiting movement of the cylindrical part from the openable position when the closure member is moved beyond the openable position and the flow path is open.

8. The device of claim 1, wherein the cylindrical part and the closure member are associated with the first of said housing parts, the axial movable piston of the second of said housing parts having a threaded bore therein, the closure member having a threaded nut on the second end face thereof engageable in the threaded bore of the piston of the second of said housing parts, the actuatable member effective to move the closure member and the axially movable piston of the second of said housing parts as a unit when the closure member is threaded into the threaded bore.

9. The device of claim 1, wherein the axially movable pistons are movable from a first end position in which the flow path is closed and in which the housing parts are separable and a second end position in which the flow path is open when the housing parts are coupled.

10. The device of claim 9, including locking means associated with connecting means connecting the housing parts in coupled relation, the locking means effective to lock the housing parts together when the pistons are in the second end position, the locking means allowing separation of the housing parts when the pistons are in the first end position.

11. The device of claim 10, wherein the connecting means comprises a coupling sleeve fixed to a housing part and rotatable therewith, the sleeve being connectable with the other of said housing parts, the connecting means including an actuating ring which, when the locking means prevents separation of the housing parts is freely rotatable with respect to the coupling sleeve and means preventing rotation between the coupling sleeve and the locking means when the locking means is in a released position.

12. The device of claim 10, wherein the connecting means comprises a coupling sleeve fixed to a housing part and rotatable therewith, the sleeve being connectable with the other of said housing parts, the connect ing means including an actuating ring which when the locking means locks the housing parts together, is freely rotatable with respect to the coupling sleeve and means for connecting the coupling sleeve with the locking means when the locking means is in a released position, the coupling sleeve comprises a screw cap.

13. The device of claim 10, wherein the locking means has a locking position and a release position, the connecting means comprising a coupling sleeve fixed to one of said housing parts and rotatable therewith, the sleeve being connectable with the other of said housing parts, the connecting means including an actuating ring which is freely rotatable with respect to the coupling sleeve when the locking means is in the locked position and which is attached to the coupling sleeve for rotation therewith when the locking means is in the release position, the actuating ring axially movable between end positions, the actuating ring positively connected with the coupling sleeve for rotation therewith in one end position.

14. The device of claim 10, in which said locking means includes a locking element cooperating with inclined cam faces of an actuating ring in such a manner that the actuating ring is kept in a disconnected position when the locking element is held in a locked position.

15. The device according to claim 10, in which said locking means comprises pins radially slidable in one of said housing parts and associated with an actuating ring, said slidable pins engaging with one other end a conical cam face of said actuating ring, the locking pins adopted to be engaged at another of their ends by a portion of one of said axially movable pistons when the piston is in a position in which the path of flow in the valve body is open. 

1. A flow control coupling for transferring contaminated media from one container to another comprising first and second separate housing parts having end faces couplable together in abutted position and releasable means for maintaining the coupled housing parts in coupled abutted relationship, each of said housing parts having coaxial equal diameter bores therein receiving axially movable pistons, one of said pistons having a cylindrical part with a bore therein closed at one end by a first end face of a separate, independently movable, closure member, the closure member attached to an actuatable member axially movable within the bore of the cylindrical part, a second end face of the closure member forming an end surface of the first housing part when the housing parts are separated, a flow path through said housing parts closable by said closure member when the first end face of the closure member closes the bore of the cylindrical part, the closure member movable away from the cylindrical part to open the bore and the flow path when the housing parts are coupled together, the closure member movable into the bore of the second housing part.
 2. The device of claim 1, wherein the actuatable member comprises an actuating rod extending through the cylindrical part and having one end thereof attached to the closure member.
 3. The device of claim 1, wherein the actuatable member comprises a tube forming a flow channel, the tube extending through the cylindrical part, the tube having transverse flow ports disposed within said cylindrical part, the tube having one end thereof attached to the closure member, and portions of the tube containing the transverse flow port projectable from the cylindrical part.
 4. The device of claim 1, including means urging the closure member against the cylindrical part to maintain the bore of the cylindrical part closed by the first end face.
 5. The device of claim 4, wherein the cylindrical part is slidable within the associated housing part and has means associated therewith limiting movement of the cylindrical part whereby the cylindrical part and the closure member are movable together in sealed relationship for a limited distance with respect to the housing part in a first direction, the closure member movable beyond the cylindrical part in the first direction.
 6. The device of claim 5, wherein means are provided preventing movement of the closure member independent of the cylindrical part until the cylindrical part has moved to a fixed position.
 7. The device of claim 5, wherein the cylindrical part is movable from a closed position to an openable position and means are provided for moving the closure member with the cylindrical part in sealed relationship therewith from the closed position to the openable position, the closure member being movable beyond the openable position to open the flow path when the cylindrical part is in the openable position, and means inhibiting movement of the cylindrical part from the openable position when the closure member is moved beyond the openable position and the flow path is open.
 8. The device of claim 1, wherein the cylindrical part and the closure member are associated with the first of said housing parts, The axial movable piston of the second of said housing parts having a threaded bore therein, the closure member having a threaded nut on the second end face thereof engageable in the threaded bore of the piston of the second of said housing parts, the actuatable member effective to move the closure member and the axially movable piston of the second of said housing parts as a unit when the closure member is threaded into the threaded bore.
 9. The device of claim 1, wherein the axially movable pistons are movable from a first end position in which the flow path is closed and in which the housing parts are separable and a second end position in which the flow path is open when the housing parts are coupled.
 10. The device of claim 9, including locking means associated with connecting means connecting the housing parts in coupled relation, the locking means effective to lock the housing parts together when the pistons are in the second end position, the locking means allowing separation of the housing parts when the pistons are in the first end position.
 11. The device of claim 10, wherein the connecting means comprises a coupling sleeve fixed to a housing part and rotatable therewith, the sleeve being connectable with the other of said housing parts, the connecting means including an actuating ring which, when the locking means prevents separation of the housing parts is freely rotatable with respect to the coupling sleeve and means preventing rotation between the coupling sleeve and the locking means when the locking means is in a released position.
 12. The device of claim 10, wherein the connecting means comprises a coupling sleeve fixed to a housing part and rotatable therewith, the sleeve being connectable with the other of said housing parts, the connecting means including an actuating ring which when the locking means locks the housing parts together, is freely rotatable with respect to the coupling sleeve and means for connecting the coupling sleeve with the locking means when the locking means is in a released position, the coupling sleeve comprises a screw cap.
 13. The device of claim 10, wherein the locking means has a locking position and a release position, the connecting means comprising a coupling sleeve fixed to one of said housing parts and rotatable therewith, the sleeve being connectable with the other of said housing parts, the connecting means including an actuating ring which is freely rotatable with respect to the coupling sleeve when the locking means is in the locked position and which is attached to the coupling sleeve for rotation therewith when the locking means is in the release position, the actuating ring axially movable between end positions, the actuating ring positively connected with the coupling sleeve for rotation therewith in one end position.
 14. The device of claim 10, in which said locking means includes a locking element cooperating with inclined cam faces of an actuating ring in such a manner that the actuating ring is kept in a disconnected position when the locking element is held in a locked position.
 15. The device according to claim 10, in which said locking means comprises pins radially slidable in one of said housing parts and associated with an actuating ring, said slidable pins engaging with one other end a conical cam face of said actuating ring, the locking pins adopted to be engaged at another of their ends by a portion of one of said axially movable pistons when the piston is in a position in which the path of flow in the valve body is open. 